hi guys, i have a 99 expedition with the 4.6 with 190k and its time for a new transmission, my plans are to supercharge the expy sometime next year, would the 4R70 hold up to the supercharger? or would the 4R100 be a better option? do you guys know what would it take to go from 4R70 to 4R100? thanks for the help

 

any help guys?

 

You will have to find out if Ford even put a 4r100 behind a 4.6l. If they didn't, you might be out of luck. I have not seen one. If the 4.6l has the same bolt pattern as the 5.0l, then you would be able. Personally, I would keep the 4r70 and stick some money in that. From what I've seen, the 4r100 has many more weak points and problems. There are all kinds of Mustangs running around with aode's and 4r70's and they work fine.

 

Work your trans over. You wouldn't just bolt in a junkyard trans after you put a huffer on your motor, would you? You'd go through it. So go through the existing trans.

Here's some folks who can tell you more:

http://www.transmissioncenter.net/AOD.htm
scroll down, 4R70 parts are there.

http://www.becontrols.com/products/aodecat.htm

http://www.tciauto.com/Products/Ford/ford_aod.asp

 

It would be a big hassle to do the swap. The wiring harness is going to be different. I think I would put the puffer on the 4.6 and see what fails first in the 4r70 and go from there.

 

thanks everybody, yeah, i looked into it and i think it would be too much of a hassle and a built 4R70 should be strong enough to handle the power i heard

 

If you are going to stay with the 4r70, do some checking around before you jump in. The more research and questions you ask now will pay big in the end. Use a reputable builder.

 

thanks, i will, 85e150six4mtod posted some links for 4R70 parts, anybody know a good transmission company? or a good rebuild kit that i can have my local guy install?